Quick comparison between both with source as being iBasso DX100 and SONY NW-A46 Walkman.
Bass: DM6 has more authority in bass region than the Tenhz P4 Pro. Both have the same amount of details here.
Update: The bass now becomes neutral with the use of supplied wide bore ear tips, previously the tips I used was the narrow bore ear tips with pink color inside.
Mids: Mids of DM6 has more smoother approach, though it is not recessed at all but when I compare it to P4 Pro, it feels that P4 Pro has more open mids because of neutral mid-bass. P4 Pro has slightly more focussed mids or I dare to say has very slighty more presense on upper mids but still neutral without being shouty at all.
Treble: DM6 has definitely smoother treble whereas treble of P4 Pro is neutral. No one has bright treble at all.
Separation: DM6 seems to have better separation and layering of instruments being slightly warm. I would say Tenhz P4 Pro also have good separation. Its a close call.
Tonality:
DM6: Neutral-warm (Narrow bore ear tips with pink color bore) and Neutral (with the supplied wide bore ear tips)
P4 Pro: Neutral
I personally like P4 Pro more because I am more of a neutral-head. But when I put DM6 into my ears, I keep listening to it as well.
[Update]: I am now liking both the IEMs equally after when I put the wide bore ear tips on the DM6..
More detailed impressions after the 100 hours of burn-in period.